1. Field of the Invention
The present invention relates to a coupling assembly used, for example, in transferring fluid (i.e., gases and/or liquids such as high purity chemicals like an etching liquid used in production of semiconductors) from a storage tank of its production plant to a tank lorry.
2. Description of the Related Art
In general, a conventional coupling assembly used in the above mentioned field comprises a stationary female or socket member and a movable male or plug member which is axially aligned with the socket member in coupling operation thereof. In this coupling operation, the male or plug member is inserted into the female or socket member so that these members are connected with each other in a fluid-tight or liquid-tight manner, as is disclosed, for example, in Japanese Utility Model Publication No. 1-10557.
In the conventional coupling assembly described above, the female and the male member of the assembly are connected with each other exclusively through a user's manual operation. In case that the coupling assembly is of a small-diameter type, it is possible for the user to manually perform its coupling operation easily. However, in the case where the coupling assembly is of a large-diameter type, it is very difficult for the user to manually perform its coupling operation, since a considerably large effort is required of the user to complete the coupling operation of such large-diameter coupling assembly.